not unlike a mushroom stamp, a stampon is the sexual act where the male removes his penis from the females menstrating vagina and strikes the female in the face or forehead, leaving a red stamp in the shape of the penis.

called a stampon due to the penis acting as a temporary tampon and also being used as a stamping utensil.

My girlfriend told me she was menstrating while we were having sex. Angered, I pulled myself out and gave her a stampon to show my disapproval.